TOPIC: Chromecast on NanoAVR HDA

Hi,

Has anyone tested to use a Chromecast --> NanoAVR --> NanoAVR out --> TV in? (I don't have one, but if it works, I would by one for sure.)
If so, will the chromecast dongle decode a DTS or DD encoded signal into a multichannel LPCM signal (which is demanded by the NanoAVR), or only in to allready downmixed stereo LPCM?

There is more than one advantage to it:
1. Stream music trough the nanoAVR HDA --> old receiver with analog 7.1 input without having my TV on.
2. It would be an awesome idea to be able to downmix, route and filter a proper LPCM signals with the nanoAVR.
3. TV's without ARC are not able to decode DD or DTS to LPCM and provide it to the NanoAVR (my situation, and I many more with this issue I guess)

If anyone would test this, I'd be very thankful.

@ Matthijs

We unfortunately don't have a chromecast, but it would indeed be a neat application. Can you do multichannel PCM on a chromecast?
That's the key information to figure out here really.

DevTeam

Thanks for the answer DevTeam,

I will test it tonight, and post results. Was able to borrow a Chromecast (1) from a friend of mine...
Key info indeed is to see if it will detect that nanoAVR does not accept DD or DTS, and outputs multichannel LPCM as result...

Best regards,
Matthijs

Yes, it is possible! However, there are some downsides.

The way I managed:
- Insert the Chromecast stick into input 1 of the NanoAVR. Toggle the HDMI input selection was needed because it didn't "see" the Chromecast dongle immediately.
- I used BubbleUPNP to stream a MKV file from my NAS to Chromecast. At first try, no audio. Then I found in the Bubble UPNP Settings(->Chromecast->Transcode settings), that there is the option to transcode formats which are not supported by Chromecast. After installing this transcode option, I could see multichannel LPCM was working. I was able to route/mix/ all channels to taste.

One big downside! The local transcoding made almost all of my video's stutter. The reason for seems to be the bandwidth of the WiFi reception of the Chromecast (I will buy a Chromecast 2 and hope that this will be better). There is also the option to install BubbleUPNP server on the NAS or computer. I will investigate more into that, and update this topic ASAP.

@ Matthijs

Thanks much for the info. If I understand right, without the transcoder, you wouldn't be able to output multichannel PCM. Is that correct?

Thanks again for all your good info for the community!

DevTeam

@ DevTeam, that's right. Without transcoding, no multichannel audio or even no audio at all with certain formats.
It all depends on the audio format used within the media container (e.g. MKV)

In short:
The Chromecast does not support DTS or Dolby Digital. It does not convert it to LPCM, neither does it pass it these compressed formats trough (allthough this wouldn't make a difference since the nanoAVR is not able to decode these formats either)

To work around this issue, there are ways to decode the audio into LPCM 5.1 before casting it to the Chromecast. (allthough this has nothing to do with NanoAVR directly, it solves the issue).

However, because the transcoded format (LPCM is raw lossless streams) makes the data transferring HUGE, the wifi connection will be the weakest link in the chain.

I bought a Chromecast 2 dongle, which handles the wifi better. I have less stuttering issues now, but it isn't gone.

I tested it in two ways:
1. Local transcoding (phone does this, and then sends the video+transcoded sound to the Chromecast
2. Installed bubbleUPNP server on the NAS, and let the audio be transcoded on the NAS instead.

The issue however remains for some 1080p Content, due to WIFI bandwidth.

But it isn't all bad, it handles stereo pcm very well (e.g. Mp3 music usingn dlna, tunein, etc.) without the need to have the TV on.

A last to-do option would be to connect the chromecast to the network using a Chromecast ethernet adapter. This would increase the reliability of the network connection, and maybe the bandwidth...

I hope this information is usefull for others. In the meanwhile I would be very interested if somebody found a better way to handle this, either with another multimedia stick or another method.

Regards,
Matthijs

Matthijs wrote:
Would XBMC/Kodi on a RaspBerry Pi possibly be a solution?

The other option would be to use a Blu-ray player or similar with UPnP capability - I think my Oppo will do it.

In either case it seems that you might need a wired connection.

I've only played with this stuff for fun. If you had a link to a short 1080p test file I could try those (above).

BTW for Wifi it helps a lot if you assign your wireless channel to an unused one. If you can find one anyway (not too many neighbors). I used an Android app called... um, Wifi Network Analyzer. heh

@ John,
Found some DTS test files over here:
download.openbricks.org/sample/HD-Audio/

Im curious if your media player wil work...

A raspberry pi with Kodi might handle it ok I guess, if it can transcode stuff to LPCM. I must say i don't have one to test it.

Another thing i was concidering is something like a windows mini pc/stick. This will run anything possible with some tweaking..

Changing the wifi channel might be an ok solution. I will try this. (I wonder though, wouldn't a wifi router seeks automatically for the strongest channel? )

Hi Matthijs, I don't know the answer to the auto channel assignment question, with my now-old Airport Extreme it didn't seem to do a very good job with picking the channel automatically, doing it manually gave a better result.

Now, with regard to transcoding, I downloaded the speaker test file from the link you gave onto a USB stick. Plugged into a Rpi 2 (*1) with Kodi 15.2 on OpenELEC running, it played back no problems on all channels. (*2) The output from the RPi 2 was plugged into a nanoAVR (*3).

*1. I think it probably important to have the Rpi 2 for processing power
*2. I don't have 71, but 5.1 with the rear surrounds mapped to the side surrrounds in the nanoAVR HDA
*3. Actually a nanoAVR DL into a nanoAVR HDA then into power amps

Hope that helps - ? I'm thinking the key issue here is the transcoding, wireless bandwidth issues you will need to investigate at your end.

J

Hi John,

Thanks for testing!
*1. Seems that Rpi+Kodi does transcoding to LPCM out of the box? (that's great!)
*2. Sam here... But I don't mind, because most content only contains 5.1 channels (by the way, I think >4 channels is overrated, better use the other channels for multisubs;)
*3. Nifty solution!

In my humble opinion, I think the key issue is the need for transcoding. @devTeam, will the nanoAVR be ever able to decode compressed 5.1 content itself? Even my blu ray player is not able to output LPCM;)
Wifi bandwidth issues due to transcoding is very common, because streaming decoded content is huge. If however transcoding or decoding is done after the streaming, the issue doesn't exist.

Note that Google sells a power supply which allows you to connect the chromecast to ethernet cable, which should eliminate any bandwidth issue.

edit- i see someone mentioned this already....

Matthijs wrote:
Yes we understand this.. Problem is more than decoding = very high licensing fees + additional DSP power (i.e. would need dual DSP) . It's not as "easy" as it sounds. Very odd that your blueray player isn't able to do PCM out.. we have yet to see this to date.. are you sure?
Which brand is that? Most player we've ever seen are all doing PCM.. That's a very basic feature knowing they already have their decoder embedded for analog out.

Devteam

devteam wrote:
I understand the issue. I'm already happy with what it does at the moment.
My bluray player is a Samsung. I am exaggerating a little bit here. It is possible to output PCM stereo with it. However, it does not doe multi channel LPCM (maybe I have to look a little bit better). Not a really big deal because i'm working to a multisub solution with stereo (so 2.4 setup). But still it would be nice to do my own stereo downmix (e.g. phantom center etc.)

while all blue ray players appear to still output pcm, almost all will only do so in stereo downmix. none of the sony players do 5.1, and budget players from the other brands will mix to stereo as well. I had to replace my brand new sony with a pricier samsung to get 5.1 pcm.
worth it for the dirac, but an added headache and expense.
Sadly, it appears the market is dropping 5.1 pcm conversion, which in a few years could mean decoding will have to be done in the minidsp.